Question
( frac{S_{1}-s_{3}}{1-S_{2}} )
( tan left(A+B+C=frac{tan A+tan B+tan C-tan A cdot tan B cdot tan C}{1-tan A cdot tan B-tan A cdot tan (-tan theta-tan C}=0right. )
R tan ( (theta+2 theta+3 theta)=0 )
( tan (6 theta)=0 )
( 6 theta=pi, 2 pi, 3 pi, 4 pi, 5 pi, 6 pi-ldots .35 pi )
( theta=frac{pi}{6}, frac{2 pi}{6}, frac{3 pi}{6} .-frac{35 pi}{6} )

In (0, 6T), find the number of solutions of the equation tano + tan 20 + tan 30 = tan e.tan20.tan30
Solution
